Bag structure

ABSTRACT

The present invention is related to a bag structure. The bag structure comprises a front panel, two lateral panels, a bottom panel, and a rear panel, and all panels join together to form the bag. Two lateral edges of the bottom panel have an extension flap for joining to the lateral panel, respectively, and a valley fold portion is between the bottom panel and the extension flap. After the bag structure is folded, the bag structure has a one-piece bottom and the flat front and rear panels, thereby having attractive appearance and strong structure and being flat when stacked.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates a bag structure. More particularly, a bag structure has a flat outward facing surface for showing advertisements perfectly with closed bottom after the bag structure is folded and collapsed.

2. Description of Related Art

In daily shopping, salesclerk usually delivers the goods to a consumer with a free convenient handbag. According to different material, the handbag is divided into plastic bag and paper bag. However, after use, discarding plastic bags become trash and are difficult to process. Furthermore, when the high quality goods are put into the plastic bag, it feels that they seem to lose their value. Therefore, the salesclerk provides a free paper handbag with advertisements printed on the outward facing surface.

Please refer to FIG. 7. FIG. 7 is a diagram of a most common used handbag 7 of prior art. The handbag 7 comprises a rectangular front sheet 71 and back sheet 72, two foldable lateral sheets 73, a bottom sheet 74, and an opening 75. A folding line 731 is provided in the two lateral sheets 73, respectively, for folding the two lateral sheets 73 inwardly between the front sheet 71 and the back sheet 72. The bottom sheet 74 is formed by folding and gluing an open flap extending from the front sheet 71, the back sheet 72, and the two lateral sheets 73. A crease 76 is provided in the back sheet, which extends to two lateral edges of the back sheet, for folding the rectangular bottom sheet 74 toward the back of the bag in a flat state. When it is intend to use the bag described above, the two lateral sheets 73 is expanded by separating the front sheet 71 and the back sheet 72, and the bottom is flattened out to form a bag with a rectangular storage space. However, the bag described above has some disadvantages described below.

-   -   1. Because the bottom is folded to the back of the bag so that         the bottom is thicker than the opening in collapsed state.         Therefore, when the bags are collapsed and stacked, the stacked         bags is not flat and is in an inclined state.     -   2. When the advertisements are printed on the front and back         sheets, the advertisements printed on the back sheet are not         attractive because of the crease for folding the bottom to the         back of the bag.     -   3. In general, when the goods are put in the bag, the weight of         the goods is mainly supported by the bottom of the bag. However,         the bottom of the traditional handbag is not integrated with the         front and back sheets when the folded structure of the         traditional handbag is formed in the stereoscopic state. The         bottom of the traditional handbag is formed by folding the flaps         extending from the front, back, and lateral sheets and gluing         flaps together by adhesive, thus the weight supporting limit of         the bottom is decreased to result that the bottom unexpectedly         breaks as the goods in the bag. Moreover, uncertain adhesion due         to human factors in gluing process may cause the problem that         the bottom can not support the weight of the goods.

Because of the foregoing disadvantages, the Taiwan Patent application with the Patent No. M365328 “Improvement of bag structure” is provided. According to this patent, a paper bag is folded and formed by folding the both sides of a default hollow bag inwardly so that the both edges of the default hollow bag form an opening with a V shape outwardly and gluing the bottom. The improvement is described below. A bottom join segment with folding line is extended from the lower end of two lateral sides of the hollow bag, respectively. In addition, a first join segment is extended from the lower end of the front sheet and the width of the first join segment is half of that of the bottom, and an inward foldable second join segment is extended from the lower end of the back sheet and the width of the second join segment is the same as that of the bottom. When the bottom of the hollow bag is assembled and folded, the bottom join segments extended from the two lateral sides are folded inwardly, then, the first join segment extended from the front sheet is closed to the bottom join segments and glued, finally, the second join segment extended from the back sheet is closed to the first join segment and glued to form a paper bag with an inward foldable bottom, thereby increasing the folding assembly efficiency of the bottom of the bag. Moreover, the friction between the bottoms and the outward facing surface of the bag is not occurred during stacked bags delivery to keep the printed picture on the bag completely.

However, the bottom of the foregoing structure is still formed by adhesion; the problem of decrease of the weight supporting limit of the bottom as the foregoing third point described also exists.

SUMMARY OF THE INVENTION

The object of the present invention is to provide a bag structure. More particularly, in view of the foregoing disadvantages of the appearance of the traditional bag and the foregoing disadvantages of the traditional bag when it is stacked, the object of the present invention is to provide a bag structure has flat front and rear panels for showing advertisements perfectly and being stacked flat by a closed bottom.

Accordingly, a bag structure is provided, comprising a front panel, two lateral panels, a bottom panel, and a rear panel. All panels join together to form the bag. Two lateral edges of the bottom panel have an extension flap for joining to the lateral panel, respectively, and a valley fold portion is between the bottom panel and the extension flap. After the bag structure is folded, the bag structure has a one-piece bottom and the flat front and rear panels, thereby having attractive appearance and strong structure and being stacked flat.

According to an embodiment of the present invention, a folding line in the center of the bottom panel extends in opposite directions up to the extension flap, when folding the valley fold portion down along the folding line, the bag is collapsed with the one-piece bottom and has the flat front and rear panels.

According to another embodiment of the present invention, the front panel and the rear panel have a hole, respectively, and a handle is fixed in the hole for being a carry bag.

According to another embodiment of the present invention, the front panel and the rear panel have a hole with kidney shape, respectively, for user carrying on.

A bag structure, under unfolding state, is also provided and comprises a front panel, two lateral panels, a bottom panel, and a rear panel. The two lateral panels are expended integrally from two opposite edges of the front panel, respectively. The bottom panel is extended integrally from the lower edge of the front panel, and two lateral edges of the bottom panel have a valley fold portion which is downward foldable, respectively, and an extension flap is extended from each valley fold portion. The rear panel is extended integrally from the bottom panel opposite to the front panel, and two lateral edges of the rear panel have a join panel for joining to the lateral panels, respectively, to form the bag.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a three-dimensional diagram of a bag structure according to an embodiment of the present invention;

FIG. 2 is a diagram of a bag structure under unfolding state according to the embodiment of the present invention;

FIG. 3 is a diagram of a bag structure according to the embodiment of the present invention in one of stages of its production;

FIG. 4 is a diagram of a bag structure under folding state according to the embodiment of the present invention;

FIG. 5 is a diagram of a bag structure according to the first embodiment of the present invention;

FIG. 6 is a diagram of a bag structure according to the second embodiment of the present invention; and

FIG. 7 is a diagram of a traditional handbag of a prior art.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

First, please refer to FIG. 1 and FIG. 2. FIG. 1 is a three-dimensional diagram of a bag structure according to an embodiment of the present invention. A bag comprises a front panel 1, two lateral panels 2, a bottom panel 3 and a rear panel 4. All panels join together to form the bag (A).

The bottom panel 3 is integrated with the front panel 1 and the rear panel 4, and two lateral edges of the bottom panel 3 have a valley fold portion 31 which is downward foldable, respectively. An extension flap 32 extends from each valley fold portion 31 for joining to one of the lateral panels 2. When the bag (A) is formed, two lateral edges of the bottom panel 3 is folded down to shape the valley fold portion 31 to form the one-piece bottom, and the bag has the flat front and rear panels, thereby having attractive appearance and strong structure and being stacked flat.

As shown in FIG. 2, the bag structure is folded from a develop blank when it is made. The bag (A), under unfolding state, comprises:

-   -   a front panel 1;     -   two lateral panels 2 is extended integrally from two lateral         edges of the front panel 1, respectively;     -   a bottom panel 3 is extended integrally from the lower edge of         the front panel 1, and two lateral edges of the bottom panel 3         have a valley fold portion 31 which is downward foldable,         respectively, and an extension flap 32 is extended from each         valley fold portion 31 for joining to one of the lateral panels;     -   a rear panel 4 is extended integrally from the bottom panel 3         opposite to the front panel 1, and two lateral edges of the rear         panel 4 have a join panel 41 for joining to the lateral panels         2, respectively, to form the bag (A).

Please refer to FIG. 1 to FIG. 4. When the bag structure is folded, the bottom panel 3 is integrated with the front panel 1 and the rear panel 4. Then, the join panels 41 at the two lateral edges of the rear panel 4 are joined to the two lateral panels 2, respectively, and the extension flaps 32 at the bottom panel 3 are also joined to the two lateral panels 2, simultaneously, thereby forming the bag. Certainly, a reinforcement member can be lined with the front panel 1, the rear panel 4 and the two lateral panels 2 adjacent the open top edge portion of the bag (A) for increasing the strength and stereoscopic effect of the opening of the bag (A).

When the bag structure is folded and collapsed for storage, the valley fold portion 31 at two lateral edges of the bottom panel 3 are folded downward for closing the front panel 1 and the rear panel 4 of the bag (A), thereby the bag (A) having a one-piece bottom and the flat front panel and rear panel after the bag is folded for storage. When the bag (A) is stacked, the top and the bottom of the stacked bags are flat and are not in inclined state, and the advertisements printed on the front panel 1 and the rear panel 4 can be shown completely for attractive appearance. Furthermore, the one-piece bottom has strong structure for bearing the weight of the goods in the bag.

Please refer to FIG. 5 and FIG. 6. The bag (A) can be provided for user carrying on. As the first embodiment, the front panel 1 and the rear panel 4 have a hole (B), respectively, and a handle 5 is fixed in the hole (B) for being a carry bag. As the second embodiment, the front panel 1 and the rear panel 4 have a hole (C) with kidney shape, respectively, for user carrying on, and the bag (A) becomes a carry bag. 

What is claimed is:
 1. A bag structure, comprising: a front panel; two lateral panels; a rear panel; and a bottom panel, integrated with the front panel and the rear panel, and two lateral edges of the bottom panel have a valley fold portion, respectively, wherein an extension flap extends from each valley fold portion for joining to the lateral panel and folding down to shape the valley fold portion for forming the bag with that the front panel and the rear panel are flat; and wherein all panels joined together to form the bag.
 2. The bag structure as claimed in claim 1, wherein a folding line in the center of the bottom panel extends in opposite directions up to the extension flap, when folding the valley fold portion down along the folding line, the bag is collapsed with the one-piece bottom and has the flat front panel and the flat rear panel.
 3. The bag structure as claimed in claim 2, wherein the front panel and the rear panel have a hole, respectively, and a handle is fixed in the hole for being a carry bag.
 4. The bag structure as claimed in claim 2, wherein the front panel and the rear panel have a hole with kidney shape, respectively, for user carrying on.
 5. A bag structure, under unfolding state, comprising: a front panel; two lateral panels, extended integrally from two opposite edges of the front panel, respectively; a bottom panel, extended integrally from the lower edge of the front panel, wherein two lateral edges of the bottom panel have a valley fold portion which is downward foldable, respectively, and an extension flap is extended from each valley fold portion for joining to one of the lateral panels; and a rear panel, extended integrally from the bottom panel opposite to the front panel, wherein two lateral edges of the rear panel have a join panel for joining to the lateral panels, respectively, to form the bag.
 6. The bag structure as claimed in claim 5, wherein a folding line in the center of the bottom panel extends in opposite directions up to the extension flap, when folding the valley fold portion down along the folding line, the bag is collapsed with the one-piece bottom and has the flat front panel and the flat rear panel.
 7. The bag structure as claimed in claim 6, wherein the front panel and the rear panel have a hole, respectively, and a handle is fixed in the hole for being a carry bag.
 8. The bag structure as claimed in claim 6, wherein the front panel and the rear panel have a hole with kidney shape, respectively, for user carrying on. 